# Php check for invalid characters

**URL:** <https://forum.kirupa.com/t/php-check-for-invalid-characters/254849>\
**Category:** Uncategorized\
**Created:** [March 16, 2008, 9:06am UTC](https://forum.kirupa.com/t/php-check-for-invalid-characters/254849 "2008-03-16T09:06:51Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Utech22](https://avatars.discourse-cdn.com/v4/letter/u/f17d59/32.png) [@Utech22](https://forum.kirupa.com/u/Utech22)\
**Post date:** [March 16, 2008, 9:06am UTC](https://forum.kirupa.com/t/php-check-for-invalid-characters/254849/1 "2008-03-16T09:06:51Z")

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I want to validate each fields by checking for invalid characters  
such as [! # $ %& '\* + - / =? ^]  
What is the best way to go about it.